1. Field of the Invention
This invention relates to a device for controlling a lens shutter and, more particularly, to a shutter control device suitable for flash photography.
2. Description of the Prior Art
Conventional lens shutter cameras have been so designed that the shutter-closing time during flash photography is set substantially at a limit whereby the effects of camera shake can be ovbiated (at a shutter speed of 1/f (focal length)) during flash photography and a fully-opened shutter condition is ensured.
Since this limit for obviating the effects of camera shake (hereinafter expressed as "camera-shake limit") changes as the focal length of a variable focal length camera changes, it is necessary to set the shutter-closing time such that the shortest possible shutter-opening duration (at the camera-shake limit for employing the longest focal length) is selected from those limits defined with respect to a series of such camera-shake limits at various focal lengths.
However, as a consequence of the foregoing, the shutter speed becomes undesirably high during short-focal-length photography so that a dimly lit background in the resulting photograph becomes completely dark because of considerable under-exposure even if a flash is used.